Vehicle Electronic Control Unit PWM Control Switching
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
In electric vehicles with power conversion devices and electric motors, the longer pulse signal generation period in existing techniques leads to lower responsiveness and increased likelihood of overcurrent or overvoltage occurrences when abnormalities occur in voltage or current sensors.
Innovation Solution
Implementing an electronic control unit that switches between first and second PWM controls, limiting the execution of the second PWM control when sensor abnormalities are detected, which generates pulse signals based on voltage commands and modulation factors, thereby reducing the risk of overcurrent or overvoltage by prioritizing shorter pulse signal generation periods.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Loss of energy
If second PWM control is used to reduce power loss, then energy efficiency is improved, but responsiveness decreases and overcurrent/overvoltage risk increases when sensor abnormalities occur
Solution Approach 1:
The system dynamically switches between first PWM control and second PWM control based on sensor status. When sensor abnormalities are detected, the system transitions from second PWM control (which has lower responsiveness) to first PWM control (which has higher responsiveness), allowing the control strategy to adapt to changing operational conditions and prevent overcurrent/overvoltage events
Solution Approach 2:
The system changes the control parameter (PWM signal generation method) based on sensor health status. The electronic control unit monitors sensor abnormalities and adjusts the PWM control mode accordingly, switching from the more efficient but less responsive second PWM control to the more responsive first PWM control when needed, thus balancing energy efficiency with safety
2Loss of energy
If second PWM control is used with longer pulse signal generation period, then power loss is reduced, but responsiveness and trackability decrease
Solution Approach 1:
The system dynamically adjusts the pulse signal generation period by switching between control modes. During normal operation, second PWM control with longer periods is used to reduce power loss. When sensor abnormalities occur or rapid response is needed, the system switches to first PWM control with shorter periods, maintaining both energy efficiency and responsiveness across different operating conditions
Data Source
AI summary
A vehicle includes an electronic control unit configured to perform control of an inverter by switching a plurality of controls including: first PWM control of generating a first PWM signal of a plurality of switching elements by comparison of voltage commands of respective phases based on a torque command of a motor with a carrier voltage and switching the plurality of switching elements; and second PWM control of generating a second PWM signal of the plurality of switching elements based on a modulation factor of a voltage and a voltage phase based on the torque command and the number of pulses in a predetermined period of an electrical angle of the motor and switching the plurality of switching elements. The electronic control unit is configured to limit execution of the second PWM control when an abnormality occurs in at least one of the current sensor or the voltage sensor.